Convector



E. LwooDs May 5, 1970 CONVECTOR Filed 001;. 4. 1968 Ou w v WMM. WW @f .4Wawy@ #ma M H w W 7% 3 United States Patent Office 3,509,869 PatentedMay 5, 1970 3,509,869 CONVECTOR Ernest L. Woods, P.0. Box 1413, Hialeah,Fla.

Filed Oct. 4, 1968, Ser. No. 765,074 Int. Cl. F24c 1/00 U.S. Cl. 126-248'Claims ABSTRACT 0F THE DISCLOSURE BACKGROUND OF THE INVENTION Boats,trailers, camps and apartments often contain no heating facilities ormarginal heating facilities because they are intended either formoderate climates or for seasonal use. Yet these places normally providecooking facilities which include gas, electric or volatile liquidburners. There is a need for an economical Way to convert a cookingburner into an auxiliary or temporary household heating unit which willincrease the distribution of heated air throughout an enclosure.

Although prior art devices for increasing the radiant effectiveness of agas llame with an ernissive surface or for increasing the convectiveaction of a gas heater are well known, these devices are generallydesigned to be incorporated as a permanent or integral part of a heatingunit. They are usually adapted to function properly with only one kindof heat source.

Accordingly, one object of the present invention is to provide a compactsupplemental device to increase the convective and radiant heating froma source of heated arr.

Another object of the invention is to provide a separate convector toconvert a cooking unit into a household heating unit on a temprarybasis.

DRAWING These and many other objects will become apparent by referenceto the following description, taken in connection with the accompanyingdrawing, in kwhich the single iigure is a horizontal elevation drawing,partly in cross-section, illustrating the convector in its preferredform.

SUMMARY OF THE INVENTION Briefly stated, the invention comprises aconduit, open at the top and bottom for the passage of heated airtherethrough, having a central venturi section for accelerating thevertical flow, circumferentially spaced ports or louvers for inducingconvective flow radially outward and upward, and having a heat radiatingernissive outer surface.

DESCRIPTION Referring now to the drawing, the convector, shown generallyat 1, rests on top of an ordinary cooking burner 2 having either heatingelements or supporting grillwork elements 3, depending on the type ofheat source, which is immaterial to the present invention. The onlyrequirement is that elements 3 be spaced to allow passage of heated airor combustion gases freely upward into the convector 1.

The convector body in its preferred form is round, open at both ends,and generally conical from top to bottom. The outer wall 4 defines aflow passage with a gradually converging section 5, a more abruptlyconverging section 6, a narrow neck 7, and a diverging section 8. Flowsections 6, 7 and 8 together form a central venturi passage which issurrounded by a relatively thick wall portion 4a.

Around the body of the convector is a series of equally spaced holes 9extending upward at an angle through the Wall 4. These are preferablyformed within suitably located protuberances 10, so that ow directinglouvers 11 are formed thereby. The openings to louvers 11 are preferablylocated at the juncture or transition between the two, convergentsections 5 and 6.

An additional feature is the provision of an internal ledge 12 which,though not essential to the heating operation, is of great utility instacking the units during production or storage. The ledge 12 isslightly larger in diameter than the top of the convector so that anumber of units will nest, and may either be continuous, as shown, orinterrupted.

The convector is preferably manufactured from a castable refractorymaterial, of which there are many available types. The refractory usedshould be capable of withstanding repeated cycles of heat and cold. Aporous, highly ernissive surface is employed, rather than a reflectivesurface, in Order to increase the heating effectiveness of the unit byradiation.

The exact dimensions of the convector are not critical, yet certaindimensions and angles have been found to be desirable in practice toobtain the best results. A very effective unit has been developed whichis 8 inches in height, 7 inches in diameter at the bottom narrowing to1% inch in diameter the neck and opening back out to 4 inches diameterat the top. The included angles of the passages on either side of theneck are between and although a range of 75 to 90 may be satisfactory,depending on the type of heat source. There are four louvers openingabout halfway up the convector in 1A inch slits.

IOPERATION The convector is placed on a cooking unit which acts as asource of heated air or hot gas. The natural upward current isaccelerated by passage through the venturi section and caused tomushroom out through the surrounding space by the diverging top section.As the heated air expands and is crowded toward the venturi section, aslight pressure increase at the entrance to the converging section 6,aided by an aspirating effect due to air moving up around the outsidesurface of the convector, causes a portion of the inside gas to flowthrough the louvers 11. This induces turbulent mixing and convectivecurrents which fan upward and outward from the unit to Warm thesurrounding air. The heated air inside the convector body also increasesthe temperature of the ceramic emissive refractory material of the wallwhich radiates heat from its exterior surface to the surrounding area.

EXAMPLE A comparative test was made in a housetrailer of 2500 cubic feetusing a propane cooking stove. The use of the convector described on onecooking burner raised the temperature of the air from 50 F. to 70 F. in17 minutes. Without the convector, four cooking burners and the ovenrequired 32 minutes to achieve the same temperature rise.

Thus there has been disclosed a simple and economical means offurnishing supplemental heating =by means of a unique convector which isplaced temporarily over an ordinary cooking unit. The convector, bymeans of venturi and louvers, greatly enhances convective heating and byits ceramic walls provides radiant heating surfaces 3 as Well. Othermodications will naturally occur to those skilled in the art and it isintended to cover all such modications Within the scope of theinvention.-

What I claim as new and desire to secure by Letters Patent of the UnitedStates is:

1. A convector comprising a hollow member with an annular wall defininga iiow passage therethrough and open at the top and bottom, saidconvector passage including a bottom convergent section, an intermediatesection of greater convergence, a venturi neck section, and a topdivergent section, said sections being adjacent and coaxial with oneanother, aid member also deining a plurality of circumferentially spacedopenings through said wall and disposed near the juncture between saidconvergent sections.

2. The combination according to claim 1, wherein said convector walldeiines a plurality of external protuberances at the location of saidopenings and arranged to provide louvers for the openings which aredirected in an upwardly direction.

3. The combination according to claim 1, wherein said intermediateconvergent section and said divergent section each have an includedangle between 75 and 90.

4. The combination according to claim 1, wherein said convector walldefines internal ledge means at the juncture of said convergent sectionsand of a greater diameter than the top of the member so as to supportthe convector in nestingrfashion on top of another like convector.

5. The combination according to claim 1, wherein said convector isanintegral member of castable refractory material of high emissivity.

References Cited UNITED STATES PATENTS 650,965 6/ 1900 Campbell 126-2481,494,499 5/ 1924 ODowd. 2,755,793 7/ 1956 Keeley.

CHARLES I. MYHRE, Primary Examiner

